In the numerical analysis of structures in fire, the material models that are used have important implications on the global behavior of the structure. In concrete, a particular phenomenon appears when ... [more ▼]

In the numerical analysis of structures in fire, the material models that are used have important implications on the global behavior of the structure. In concrete, a particular phenomenon appears when subjected to high temperatures: the transient creep strain. Models integrating explicitly a term for transient creep strain have been proposed in the literature but, in the current Eurocode 2 model, there is no explicit term for transient creep strain. This phenomenon is included in the Eurocode 2 model, but it is implicitly considered in the mechanical strain term. A series of experimental fire tests on axially restrained concrete columns subjected to heating and cooling has been recently performed at South China University of Technology and described by Wu et al. (Fire Technol 46:231–249). In the original paper, it was shown that using the implicit model of Eurocode 2, the behavior of the columns cannot be simulated properly, especially during the cooling phase. The objective of the present paper is to perform again the fire tests simulations using a new formulation of the Eurocode 2 model that contains an explicit term for transient creep. In the first part of the paper, the explicit formulation of the Eurocode 2 model is presented. In the second part, the fire tests are modeled with the software SAFIR using, on the one hand, the implicit Eurocode model and, on the other hand, the new explicit model. It is shown that the transient creep model has significant implications on the global behavior of structural concrete members, as the residual axial load sustained by the columns at the end of the fire can differ by up to 25% of the initial applied load depending on the transient creep strain model that is used for the calculation. The experimental behavior is better matched with the new explicit model than with the current Eurocode model. Particularly, the results given by the Eurocode model during the cooling phase are unconservative as the residual axial load is overestimated. Finally, it is explained why, on the basis of an example, in a performance-based approach, these results can have important implications on the global fire resistance of a structure. [less ▲]

Posidonia oceanica shoots sampled from the healthy meadow in the bay of Revelatta (Corsica, France) were transplanted on metallic grids at 10 m depth. Transplanted shoots have been regularly monitored by ... [more ▼]

Posidonia oceanica shoots sampled from the healthy meadow in the bay of Revelatta (Corsica, France) were transplanted on metallic grids at 10 m depth. Transplanted shoots have been regularly monitored by the measurement of growth, biomass and C, N and P contents in the leaves and the belowground parts. After six months of experiment, the survival rates varied from 14 to 84 % on the different transplantation sites. Leaf biomass on the transplanted cuttings was lower than biomass in the control shoots but root biomass raised from December 2000 to May 2001 on the transplanted shoots. Transplant growth (8,3 +/- 2,3 mm.d(-1).shoot(-1)) after six months was similar to control growth (8,2 +/- 2,8 mm.d(-1). shoot(-1)). The C, N and P contents in transplants were significatively lower than in control shoots suggesting that transplanted cuttings are unable to meet their nutrient requirements. The modifications of the C, N, P contents in the belowground parts of the transplanted shoots indicate a mobilization of these nutrients in those compartments to produce new roots and restore a normal nutrients absorption. [less ▲]

Locomotor training on a treadmill is a therapeutic strategy used for several years in human paraplegics in whom it was shown to improve functional recovery mainly after incomplete spinal cord lesions. The ... [more ▼]

Locomotor training on a treadmill is a therapeutic strategy used for several years in human paraplegics in whom it was shown to improve functional recovery mainly after incomplete spinal cord lesions. The precise mechanisms underlying its effects are not known. Experimental studies in adult animals were chiefly performed after complete spinal transections. The objective of this experiment was to assess the effects of early treadmill training on recovery of spontaneous walking capacity after a partial spinal cord lesion in adult rats. Following a compression-injury by a subdurally inflated microballoon, seven rats were trained daily on a treadmill with a body weight support system, whereas six other animals were used as controls and only handled. Spontaneous walking ability in an open field was compared weekly between both groups by two blinded observers, using the Basso, Beattie and Bresnahan (BBB) locomotor rating scale. Mean BBB score during 12 weeks was globally significantly greater in the treadmill-trained animals than in the control group, the benefit of training appearing as early as the 2nd week. At week 7, locomotor recovery reached a plateau in both animal groups, but remained superior in trained rats. Daily treadmill training started early after a partial spinal cord lesion in adult rats, which accelerates recovery of locomotion and produces a long-term benefit. These findings in an animal model mimicking the closed spinal cord injury occurring in most human paraplegics are useful for future studies of optimal locomotor training programs, their neurobiologic mechanisms, and their combination with other treatment strategies. [less ▲]

Twenty-four acromegalic patients were treated with octreotide subcutaneously for periods of 3 to 6 weeks (group I, 12 cases) or 6 months (group II, 12 cases) before transsphenoidal surgery. Radiological studies performed in 19 patients before and at the end of this treatment period revealed no changes in 8 cases. In 8 other cases, a slight reduction in tumorsize was observed, and in 3 cases an important shrinkage was documented. At surgery, the adenomatous tissue appeared softer than in nonpretreated patients, facilitating the operation. Pathological examination revealed widening of perivascular spaces with accumulation of fibrous tissue and more crinophagy than in nonpretreated patients but failed to reveal morphologically pronounced cell involution as observed in prolactin-producing adenomas treated with dopamine agonists. No significant difference in frequency or extent of cellular changes was noted between the two groups. These morphological findings seem to be more consistent with a functional inhibition of growth hormone release than with cellular alterations induced by octreotide. [less ▲]

The belowground food web represents a major part of associated biodiversity in forest ecosystems, and plays a significant role in the ecosystem processes of litter decomposition and nutrient turnover ... [more ▼]

The belowground food web represents a major part of associated biodiversity in forest ecosystems, and plays a significant role in the ecosystem processes of litter decomposition and nutrient turnover. Past research has demonstrated overwhelming evidence of strong tree species identity effects on earthworm communities. It has been proposed that increased plant community diversity would be beneficial to the abundance and diversity of the belowground food web, but effects of tree species diversity on earthworm communities have seldom been reported, and are inconclusive. In this study at continental scale we evaluated whether tree species diversity positively affects earthworm biomass and diversity. For this purpose the FunDivEUROPE Exploratory Platform was used with 209 plots in 6 regions well spread over Europe with a low within-region site variability, but a within-region tree species diversity gradient from monocultures to 3 or 4 species plots. In every plot earthworms were sampled using a combined method of mustard extraction and hand sorting of litter and a soil monolith. Data are being analysed with multivariate tools and mixed effects models. First results suggest only limited influence of tree diversity on the biomass of earthworm communities at continental scale. Tree diversity effects are weak, context specific and interacting with tree identity. In nutrient poor soils we found a negative tree diversity effect on earthworm biomass when deciduous monocultures are enriched with coniferous species, while in rich soils we found a positive tree diversity effect which could be related with the food security this provides to the earthworm community. [less ▲]

Bulls were implanted with an ear pellet of trenbolone acetate and oestradiol in association. Some treated bulls produced a sperm without spermatozoa but there were no significant differences in ... [more ▼]

Bulls were implanted with an ear pellet of trenbolone acetate and oestradiol in association. Some treated bulls produced a sperm without spermatozoa but there were no significant differences in spermatozoa concentration and sperm quality between treated animals which produced a sperm with spermatozoa and control bulls. The scrotal circumference of the treated animals did not change over the experimental period while that of control bulls regularly increased. After a dynamic stimuation with luteinzing hormone releasing hormone, the luteinizing hormone concentrations did not change in the treated animals and the testosterone kinetic profiles were characterized by a low basal concentration and small peak heights. The microscopic evaluation of the testicles indicated a reduction in the percentage of seminiferous tubules with mature spermatozoa and a reduction in the number of Leydig cells in the islets. [less ▲]

in American Journal of Obstetrics and Gynecology (2010), 203(4), 3646-36412

OBJECTIVE: The level of tumor-associated receptor-binding cancer antigen that is expressed on SiSo cells (RCAS1) is decreased significantly in preeclamptic pregnancies. We hypothesized that RCAS1 protein ... [more ▼]

OBJECTIVE: The level of tumor-associated receptor-binding cancer antigen that is expressed on SiSo cells (RCAS1) is decreased significantly in preeclamptic pregnancies. We hypothesized that RCAS1 protein gene silencing might affect blood pressure and proteinuria in pregnant mice. STUDY DESIGN: On postcoital day 7.5, pregnant imprinting control region mice were subjected to the transfer of small interfering RNA (siRNA) against RCAS1 protein into the uterine cavity with the use of a hemagglutinating virus Japan envelope. Scramble siRNA was used as a negative control. Blood pressure and urine albumin/creatinine measurements were performed. The effect of the transferred siRNA was examined in uterine samples on postcoital day 8.5 with the use of Western blotting and immunohistochemistry analyses. RESULTS: In the RCAS1 siRNA group, blood pressure significantly raised on postcoital days 9.5, 10.5, 11.5, and 15.5, whereas urine albumin/creatinine ratio was significantly increased on postcoital day 9.5 CONCLUSION: Our results suggest the importance of RCAS1 protein in the pathophysiologic condition of preeclampsia. [less ▲]

Understanding transport processes inside stars is one of the main goals of asteroseismology. Chemical turbulent mixing can affect the internal distribution of μ near the energy generating core, having an ... [more ▼]

Understanding transport processes inside stars is one of the main goals of asteroseismology. Chemical turbulent mixing can affect the internal distribution of μ near the energy generating core, having an effect on the evolutionary tracks similar to that of overshooting. This mixing leads to a smoother chemical composition profile near the edge of the convective core, which is reflected in the behavior of the buoyancy frequency and, therefore, in the frequencies of gravity modes. We describe the effects of convective overshooting and turbulent mixing on the frequencies of gravity modes in B-type main sequence stars. In particular, the cases of p-g mixed modes in β Cep stars and high-order modes in SPBs are considered. [less ▲]

We apply a new parameterisation of the Greenland ice sheet (GrIS) feedback between surface mass balance (SMB: the sum of surface accumulation and surface ablation) and surface elevation in the MAR ... [more ▼]

We apply a new parameterisation of the Greenland ice sheet (GrIS) feedback between surface mass balance (SMB: the sum of surface accumulation and surface ablation) and surface elevation in the MAR regional climate model (Edwards et al., 2014) to projections of future climate change using five ice sheet models (ISMs). The MAR (Modèle Atmosphérique Régional: Fettweis, 2007) climate projections are for 2000–2199, forced by the ECHAM5 and HadCM3 global climate models (GCMs) under the SRES A1B emissions scenario. The additional sea level contribution due to the SMB–elevation feedback averaged over five ISM projections for ECHAM5 and three for HadCM3 is 4.3% (best estimate; 95% credibility interval 1.8–6.9%) at 2100, and 9.6% (best estimate; 95% credibility interval 3.6–16.0%) at 2200. In all results the elevation feedback is significantly positive, amplifying the GrIS sea level contribution relative to the MAR projections in which the ice sheet topography is fixed: the lower bounds of our 95% credibility intervals (CIs) for sea level contributions are larger than the "no feedback" case for all ISMs and GCMs. Our method is novel in sea level projections because we propagate three types of modelling uncertainty – GCM and ISM structural uncertainties, and elevation feedback parameterisation uncertainty – along the causal chain, from SRES scenario to sea level, within a coherent experimental design and statistical framework. The relative contributions to uncertainty depend on the timescale of interest. At 2100, the GCM uncertainty is largest, but by 2200 both the ISM and parameterisation uncertainties are larger. We also perform a perturbed parameter ensemble with one ISM to estimate the shape of the projected sea level probability distribution; our results indicate that the probability density is slightly skewed towards higher sea level contributions. [less ▲]

Eggs are a rich source of lipids and proteins. Because of their low production cost, they represent a cheap source of animal proteins and lipids. recently, in Algeria, consumers’ interest are oriented of ... [more ▼]

Eggs are a rich source of lipids and proteins. Because of their low production cost, they represent a cheap source of animal proteins and lipids. recently, in Algeria, consumers’ interest are oriented of healthiness and dietetic values food. The purpose of this study was to investigate the effects a dietary supplement of Urtica dioica on laying hen's performance and egg quality. The study was conducted from may to june 2014 in the area of Chemini (Algeria). Sixty, 25-wk-old Lohmann Brown layers were randomly divided into 3 groups with 20 hens in each group. Group 1 was the control group fed a standard commercial diet based on corn and soybean, whereas the groups 2 and 3 were fed the control diet supplemented with 1% and 1.5% of nettle respectively. The hens were housed in cages in the same local and fed ad libitum. Fifty five eggs were sampled 4 times in each group from 25 to 27 weeks. A total of 220 eggs were examined. A series of measurements were carried out on each egg, namely egg weight, form index (egg shape), yolk to albumen ratio (Y:A), Yolk color, egg shell thickness, Haugh’s units. Egg weight, yolk color and Haugh Units (HU) were affected by age. Significant differences (P<0.05) were recorded between feeding type in total egg weight, yolk color and Haugh Units. The egg from group 2 proved to have a higher egg weight (57.67g; group 1: 55.41g; group 3: 56.70g; P<0.05), (33.4%), intermediate Yolk color (8.53; group 1: 9.03 ; group 3: 9.38; P<0.05) and HU (79.81; group 1: 80.85; group 3: 76.92). The results showed that the use of 1% and 1.5% of Urtica dioica, had positive effects on the color of yolk of laying hens. Using different levels of Urtica dioica could change the characteristics of egg and could meet the preferences of consumers for the intense color of the yolk. [less ▲]